Synergistic Enhancement of Low-Temperature Self-Repairing Polyurethane Elastomers through Quadruple Hydrogen Bonds and Coordination Bonds
Jialiang Li, Yinghu Song, Guojun Song, Zhaoji Li, Xirui Yang, Shuang Yin, Xiaoru Li
Abstract
The preparation of polyurethane (PU) materials with both low-temperature rapid repair and robust mechanical properties still remains a challenging yet promising endeavor. Herein, a multifunctional linear PU supramolecular elastomer was successfully synthesized, incorporating multiple hydrogen bonds and coordination bonds to endow it with self-healing properties. The results demonstrated that the self-healing PU exhibited strong tensile strength (∼30 MPa), high elongation at break (∼925%), and excellent toughness (∼112 MJ/m 3 ) through synergistic effect of hydrogen bonds and metal coordination bonds. After 12 h of repair at 45 °C, the repair efficiency of the PU film reaches 87%. The self-repairing PU film also possesses excellent transparency with a transmittance exceeding 90%. Furthermore, the PU film demonstrates good recyclability; even after multiple recycling and reshaping, its mechanical properties do not show a significant decrease. Therefore, the development of self-healing PU with low-temperature capabilities holds significant theoretical implications, practical value, and broad application prospects. These materials are expected to find wide-ranging applications in various fields in the future.